Electrolytic capacitors are typically used in motor control applications to achieve the high capacitance needed to prevent excessive supply voltage fluctuations when switching the output stages on and off. The electrolytic capacitor acts as a nearby charge reservoir, as opposed to the vehicle battery, which is connected via wire of substantial length. Axial capacitors (having one lead per end) have higher Ripple Currents ratings, thus improved performance over radial capacitors (having both leads on the same end) of the same size, due to a reduction in Equivalent Series Resistance. One issue with electrolytic capacitors is that they cannot be subjected to typical reflow solder oven temperatures, and hence need to be manually soldered via selective wave solder or other means. Another concern with electrolytic capacitors is maintaining the capacitor in place when the capacitor is exposed to vibration, shock, or other harsh physical environments.
Furthermore, axial capacitors are prone to roll or tip either prior to, or during the selective wave soldering process during manufacturing.
Accordingly, there exists a need for a retention structure which stabilizes the capacitor during the manufacturing process, as well as prevents the capacitor from rolling out of position during the manufacturing process.